The present disclosure relates generally to the field of electrical drive systems. More particularly, the disclosure relates to techniques for operating fundamental front end (FFE) rectifiers in an electrical motor drive system using a single-phase of alternating current (AC) power.
Power rectifiers, such as FFE rectifiers, are used in a wide range of applications including electrical motor drive systems. The power rectifiers are generally designed to rectify and condition incoming three-phase AC voltage into a direct current (DC) voltage, which may be inverted back to a controllable AC voltage. The controllable AC voltage may then be used to power or drive a motor in the electrical motor drive system. In order to decrease the speed of the motor in the motor drive system, the motor drive system also includes some type of motor braking ability in which energy from the motor braking is dissipated or re-converted. That is, the energy resulting from the braking operation can either be routed to a resistor, which will dissipate the energy as heat, or routed back into a power network that supplies the motor drive system its three-phase AC voltage (i.e., source). By routing the energy created from the braking operation of the motor (i.e., regenerative energy) back to its source, the electrical motor drive system becomes an energy efficient regenerative motor drive system.
One type of rectifier (i.e., converter) widely used for regenerative motor drive systems includes an FFE rectifier. The FFE rectifier is a simple and cost effective regenerative power converter that rectifies and conditions the incoming three-phase AC voltage into a DC voltage. Additionally, the FFE rectifier includes insulated gate bipolar transistor (IGBT) switches to send regenerated energy of the motor back to its source. Generally, a motor drive system is effectively capable of driving its load while the FFE rectifier is coupled to a three-phase AC voltage source. However, it is now recognized that it may be useful to operate the motor drive system using a single-phase AC voltage source.